//2009/08/16 17:41:35
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <queue>
#include <sstream>
#include <algorithm>

using namespace std;

class Straights
{
public:
    int howMany(vector <int> hand, int k)
    {
        int sum = 0;
        for (int i = 0; i <= hand.size()-k; i++)
        {
            int prod = 1;
            for (int j = 0; j < k; j++) prod *= hand[i+j];
            sum += prod;
        }
        return sum;

    }
};
